Respiratory Syncytial Virus (RSV)

What is Respiratory Syncytial Virus? 
Respiratory Syncytial Virus (RSV) is the commonest cause of severe respiratory illness among children under 2 years of age. It is also the commonest cause of hospital admissions due to acute respiratory illness in young children. Most cases are not specifically diagnosed as RSV, however it causes 80% of bronchiolitis and 20% of pneumonia in young children. It is a significant cause of infection and outbreaks in hospitals, neonatal units, day units and nursing homes. RSV outbreaks typically occur in the winter months with peak numbers of infections usually reported in December and January every year, though the size of the peak varies from winter to winter.

What are the symptoms of Respiratory Syncytial Virus?
Symptoms can appear between 2 to 8 days after a person is infected and include fever, runny nose, sore throat, cough and sometimes croup and wheezing. Children may also get ear infections. Lower respiratory tract infection, such as pneumonia or pneumonitis, are most likely to occur during a child's first infection with RSV and may develop in 30-70% of first infections. Severe RSV infections are less common in breast-fed infants. The infectious period lasts from shortly before to 1 week after the onset of symptoms. Most children recover from illness in 8 to 15 days. Immunity is incomplete and short-lived with RSV. Repeated respiratory infections can occur, though these are usually mild and become less common with increasing age. Although RSV is primarily a childhood infection RSV infection can occur at any age and may be severe in elderly persons. 

How is Respiratory Syncytial Virus spread?
Spread occurs in the air from another person who has RSV. It is spread by that person coughing, sneezing or spitting. Spread can also occur indirectly through contact with contaminated hands, handkerchiefs, eating utensils or other objects or surfaces. Infection occurs from contact of infectious material with the mucous membranes of the eyes, mouth or nose. RSV can survive for 24 hours on contaminated surfaces.

Who is most at risk?
The highest rates of hospitalisation with RSV occur in children under 6 months, in children who have cardiopulmonary disease or who were born prematurely. About 1 in 20 older people suffer with RSV infection each year. Persons with compromised immune systems are also at risk from RSV infection.  Overcrowding and passive smoking are also recognised risk factors for infection.

How is it treated?

• No specific treatment other than treatment of symptoms i.e. paracetamol to reduce temperature is necessary for children with mild illness. Children with severe respiratory illness will require hospitalisation and oxygen therapy.
• Antiviral Medicines: Ribavirin is licensed for the treatment of RSV but there is controversy over its clinical efficacy.
• Antibodies against RSV: Palivizumab, a monclonal antibody therapy, is licensed in Ireland for the prevention of serious lower respiratory tract infection caused by RSV in infants at high risk of infection.
• Antibiotics are not effective against RSV and it is important that unnecessary antibiotics are discontinued once a diagnosis of RSV infection is confirmed, to avoid adverse drug reactions and promotion of antibiotic resistance.

Prevention

• Frequent, careful handwashing is the most important measure in preventing the spread of RSV.
• Avoiding sharing items such as cups, glasses and utensils with persons who have RSV illness should decrease the spread of the virus to others.
• In the hospital setting, RSV transmission can be prevented by
  • Managing children with RSV together in the same ward
  • Strict attention to handwashing recommendations
  • Barrier precautions, such as gowns and gloves, may be required
  • Avoid overcrowding
  • Restrict visiting if necessary
• Exclude persons ill with RSV from crèches, work, hospitals, school and non-residential institutions until well.
• Avoid young infants, frail elderly and immunocompromised coming into contact with individuals with respiratory infection.
• Vaccines for RSV are presently under development.

Last reviewed: November 2006